97 lt1 missfire on #7 i need help!
#1
97 lt1 missfire on #7 i need help!
So yes ive searched and searched and read for days and days. Ive Googled ive yahood wut ever you want to call it and still have not found a solution to my problem. 97ss camaro with le2 heads and cam new forged 355 with stock crankshaft. Ecm reprogrammed by pcm for less, 36lb injectors, new msd coil etc etc.
Ok the problem is #7 won't fire correctly. Header won't heat up to the point where if i spray water on that tube it doesn't evaporate instantly like it does on the other 7 header tubes. Thats how i found what cylinder was misfiring. So i got a spark tester and it doesn't shoot spark continually it goes on and off... Ok it goes like this ".. .... .. .. . .... . And then no spark then it comes back. Why is the optispark not sending spark constantly to that one wire? Could it be the cap and rotor? Or the optispark itself?
The car ran fine for a couple of days and a few day later it started miss firing bad. Now i started off by checking the injectors accel 36lb brand new checked the signal too with doids has signal.. Scratched that off the board when i double checked the spark on that wire with spark checker and the second time it failed so i thought its the summit racing wire thats bad. I ordered msd super-conductor wires, same thing. Spark comes and goes at time doest see no spark. Why only #7????? Why oh why. Went and bought new map sensor, started easier but still the miss is there. Is there anything else i can check before i pull the damb opti off? I bought this car broken i put alot of time into putting it together and get it running i just would like someones opinion or maybe they had the same issue and found the solution.
Oh, i just got my 02 sensors gona install them but i doubt that will fix it..
Ome more thing, when i first got it running one of the coolant hose on the water pump was leaking and spraying coolant all over the place.
Any help will be appreciated
97ss
Ok the problem is #7 won't fire correctly. Header won't heat up to the point where if i spray water on that tube it doesn't evaporate instantly like it does on the other 7 header tubes. Thats how i found what cylinder was misfiring. So i got a spark tester and it doesn't shoot spark continually it goes on and off... Ok it goes like this ".. .... .. .. . .... . And then no spark then it comes back. Why is the optispark not sending spark constantly to that one wire? Could it be the cap and rotor? Or the optispark itself?
The car ran fine for a couple of days and a few day later it started miss firing bad. Now i started off by checking the injectors accel 36lb brand new checked the signal too with doids has signal.. Scratched that off the board when i double checked the spark on that wire with spark checker and the second time it failed so i thought its the summit racing wire thats bad. I ordered msd super-conductor wires, same thing. Spark comes and goes at time doest see no spark. Why only #7????? Why oh why. Went and bought new map sensor, started easier but still the miss is there. Is there anything else i can check before i pull the damb opti off? I bought this car broken i put alot of time into putting it together and get it running i just would like someones opinion or maybe they had the same issue and found the solution.
Oh, i just got my 02 sensors gona install them but i doubt that will fix it..
Ome more thing, when i first got it running one of the coolant hose on the water pump was leaking and spraying coolant all over the place.
Any help will be appreciated
97ss
#2
Re: 97 lt1 missfire on #7 i need help!
The note about spraying water....could have gotten "in" opti. Usually that would cause misfire over various cyl
what brand of opti do you have
#3
Re: 97 lt1 missfire on #7 i need help!
Its just weird that only one cylinder is misfiring. With the boot off the sparkplug and the sprak plug tester on the new wire can clearly see its #7 not firing at times or not firing correctly. Its a summit racing opti. Yes ive herd only buy ac delco optis and i had one but it flooded during Harvey so i returned it and they didn't have any more ac delco in stock. So i bought a summit racing one. So you think its definitely the opti?
#4
Re: 97 lt1 missfire on #7 i need help!
It seems unlikely to be the OPTI at this point but it certainly could be. Look first at the wire itself...maybe even replace it with an old one if you have one around. If that turns out to not be the problem and the spark plug is known to be good, then look at the OPTI...
#5
Re: 97 lt1 missfire on #7 i need help!
It seems unlikely to be the OPTI at this point but it certainly could be. Look first at the wire itself...maybe even replace it with an old one if you have one around. If that turns out to not be the problem and the spark plug is known to be good, then look at the OPTI...
1st set of wires are summit racing new. Thought it was the cheap wires so i ordered the msd. Still the same problem.
#6
Re: 97 lt1 missfire on #7 i need help!
Given you have put 2 sets of wires on, check FI working and spark tester shows no or intermittent spark on #7.....pointing hard at Opti. The cap itself may have a defect on the #7. The caps used on the no name clones are cheap. MSD C&R is very good, not the MSD Opti though
If the Summit Opti is under warranty you can get another one and roll the dice on it.
To bad the AC Delco one you had was damaged in flood.
Occasionally rockauto has AC Delco remans
If the Summit Opti is under warranty you can get another one and roll the dice on it.
To bad the AC Delco one you had was damaged in flood.
Occasionally rockauto has AC Delco remans
#7
Re: 97 lt1 missfire on #7 i need help!
Given you have put 2 sets of wires on, check FI working and spark tester shows no or intermittent spark on #7.....pointing hard at Opti. The cap itself may have a defect on the #7. The caps used on the no name clones are cheap. MSD C&R is very good, not the MSD Opti though
If the Summit Opti is under warranty you can get another one and roll the dice on it.
To bad the AC Delco one you had was damaged in flood.
Occasionally rockauto has AC Delco remans
If the Summit Opti is under warranty you can get another one and roll the dice on it.
To bad the AC Delco one you had was damaged in flood.
Occasionally rockauto has AC Delco remans
#8
Re: 97 lt1 missfire on #7 i need help!
You only have to remove the damper/pulley portion, the hub does not have to be removed. Typical problem is rust on the hub, sometimes requires a 3-jaw or a crow foot (96/97) to get the damper/pulley loose.
http://shbox.com/1/pull_pulley.jpg
http://shbox.com/1/pull_pulley.jpg
#9
Re: 97 lt1 missfire on #7 i need help!
You only have to remove the damper/pulley portion, the hub does not have to be removed. Typical problem is rust on the hub, sometimes requires a 3-jaw or a crow foot (96/97) to get the damper/pulley loose.
http://shbox.com/1/pull_pulley.jpg
http://shbox.com/1/pull_pulley.jpg
Hopefully that will be the end of that.
Thanks for the advice
#11
Re: 97 lt1 missfire on #7 i need help!
possible ICM, more likely Opti given it is specific to # 7
Typically a ICM fail is no start or shuts off after the engine gets to temp and won't restart
If you are pulling opti, remove cap and hold up to a bright light and look for any "tracking" (arc) between the paths imbedded in cap
Typically a ICM fail is no start or shuts off after the engine gets to temp and won't restart
If you are pulling opti, remove cap and hold up to a bright light and look for any "tracking" (arc) between the paths imbedded in cap
#13
Re: 97 lt1 missfire on #7 i need help!
possible ICM, more likely Opti given it is specific to # 7
Typically a ICM fail is no start or shuts off after the engine gets to temp and won't restart
If you are pulling opti, remove cap and hold up to a bright light and look for any "tracking" (arc) between the paths imbedded in cap
Typically a ICM fail is no start or shuts off after the engine gets to temp and won't restart
If you are pulling opti, remove cap and hold up to a bright light and look for any "tracking" (arc) between the paths imbedded in cap
Forgot to mention one thing. The car flooded completely during Harvey that includes ecm. Didn't want to throw this into the mix since the car ran ok for a few days after i first started it. So im guessing the ecm survived even though it was under water.
97sswcubes
#14
Re: 97 lt1 missfire on #7 i need help!
was the pcm4less tune done after the flood?
so the opti was completely submerged also??
#15
Re: 97 lt1 missfire on #7 i need help!
Yeah wow, seems odd to mention this now. If the PCM was submerged, there isn't much of the car that wasn't (unless it was pointing severely nose down). Could even be dried silt inside the opti, disrupting the timing windows.